Trade: Filling the Ship's Hold

[atpollard]

From another Thread:

Unless the Beowulf is guaranteed to be at least 3/4 full each jump, and there is no way to guarantee that without exclusive contracts (a role play event beyond the scope of this discussion), the Marava will make more money over the course of a year.

Looking at trade from the Port's perspective:
Suppose someone wanted to transport a cargo to a world ten parsecs away along a J-1 main (assume a -4 purchase DM and +4 sale DM between those two particular worlds).

I could send it on an immediately available J-1 Free Trader that would take 10 jumps and 20 weeks to reach the destination (I hope that the cargo is not produce). I will need to pay 1000 cr per Jump for each of the 10 jumps (Per LBB2) or 10,000 cr per dTon of cargo.

I could wait for a J-2 Far Trader that would take 5 jumps and 10 weeks to reach the destination at a cost of 5,000 cr per dTon of cargo (1000 cr/jump x 5 jumps). If that particular Traveller Universe uses the common ‘1000 cr per parsec’ variant rules, then it takes 5 jumps and 10,000 credits per dTon of cargo.

Using either the 'Merchnat Prince' or LBB2 Trade systems as a guide, one would expect trade to flow between every pair of worlds that generates a positive DM with some 'thru traffic' at every system between those two trade partners. For the sake of this discussion, let’s assume that every world has some cargo bound for every world within 3 jumps.


Looking at trade from the Ship's perspective:
A ‘Beowulf’ Free Trader could be guaranteed ample cargo by filling half of the hold with cargo to a world two jumps away (the high volume trading partner) and 1/3 of the hold with a world 1 parsec away (a low volume trading partner). The hold is now 5/6 full of cargo that will pay 1000 cr per parsec (by either the official ‘per jump’ or unofficial ‘per parsec’ pricing.) When we arrive at the first world, we unload 1/3 of the hold and take on 1/4 of a hold worth of cargo that is also heading for the second world. My hold is now 3/4 full. At the high volume trading partner, cargo is plentiful and we fill 90% of the hold with cargo.

I think that a Fat Trader could keep it’s hold nearly full by just taking on cargo for multiple destinations as it travels a J-1 main. The same concept would work for a J-2 ship on a J-2 main, but the J-1 ships tend to have more trouble filling their holds.


This is not a high 'speculation' model for trade and might not be ideal for a group of 'adventurers'. It is a plausible model for an imperium full of tramp freighters just trying to keep the hold full and make the payments - the background traffic for a group without a ship trying to hitch a ride.

 

[jawillroy]

Interesting model.

Now, from the perspective of the ship:

How would you compute the availability of cargo and passengers for worlds greater than 1 jump away? Seems there would be fewer by a pretty sharp order. Maybe taking the book 2 cargo tables and adding a negative modifier per jump above 1 to get there?

Suppose you've got a type A in port, and a type M: Jump1, Jump3. Both are on planet Z.

In a jump1 main extending from Z are planets W, X, and Y. Let us assume for the purposes of this argument that none of the worlds are high or low pop, and are of a like tech level.

Both ships can make it to planet W in 1 jump, and would get the same chances of getting cargo for that trip.
If the destination was planet X, the M can do that in 1 jump, and has the same chances of getting cargo and passengers as it does for a run to planet W. The A-ship needs two jumps to get to planet X, though, resulting in a negative (let's say) -3 modifier to its passenger and cargo rolls.

If the destination was planet Y, the M can still do that in 1 jump, and has the same chances of getting cargo and passengers as it does for a run to planet W or X. The A-ship needs three jumps to get to planet Y, though, resulting in an additional -3 to its passenger and cargo rolls, for a total of -6.

Even so, if a free trader were planning a long run from planet Z to planet Y, it could 1) get a few passengers and a little cargo for distant points on the run and lot for the nearer stops; it would have a core of guaranteed cargo for the whole run, so if some of the middle legs of the trip were to backwater lay-over planets, it wouldn't have to run empty.

Although: perhaps this should be weighted favorably towards cargo. I can see someone paying for sending cargo for three jumps on the slow boat. It's harder for me to imagine a passenger paying for three jumps when he could get there faster for the price of one, UNLESS long jump passenger service is unavailable for many worlds. So perhaps the modifier for cargo should be something like -2 per extra jump, and the modifier for passengers should be -4 per extra jump.

 

[robject]

How would you compute the availability of cargo and passengers for worlds greater than 1 jump away?

If you're a LBB3 fellow, I guess you could do it the same way as typical. Never thought of it that way, but is there a rule saying otherwise?

 

[pendragonman]

AT, when writing my comments I placed cargo destined for more than 1 jump away under the "excusive contracts" (at least during my mental reasoning) due to the lack of any time dependant shipping modifiers to the tables as written. Matt and Whip's "discussion" was about shipping between planets that were J-1 apart and on a J-1 main and did not (at least overtly) concern cargos delivered along said main but to planets more than J-1 apart.

Your line of reasoning, however seems pretty sound without a time dependant variable attached.

Jawillroy, your comments about passengers is somewhat valid. If we look at a "modern model", based on airline routes, it becomes quickly clear that the faster J-3 boat will be able to charge waaaay more for its tickets to the world J-3 away than the J-1 boat due to the time to get there (Direct flights are almost always more expensive than multiple connection flights for distant destinations). That said, there will always be those passengers where money is no object but time is of the essence, and those that time is no object but money is of the essence.

Unfortunately, the rules do not specifically state that the High Pass ticket costs more on a J-3 boat to a world J-3 away. That is left for role-play.

 

[pendragonman]

If you're a LBB3 fellow, I guess you could do it the same way as typical. Never thought of it that way, but is there a rule saying otherwise?

Nope. no official modifiers exist. House rules only.

 

[jawillroy]

I've always understood that the book 2 rules provide for calculating cargo & passengers for a specific jump as opposed to an ultimate destination. I don't have the book in hand.

The way I've generally thought of it is that passengers will generally travel a jump at a time, having to arrange another ship each leg of the journey; cargo gets shipped one jump from point of purchase to point of sale; the new owner chooses how to dispose of it (end user, or selling it elsewhere.) I reckoned longer journeys require charters, or larger haulers with fixed contracts to handle a particular route. In either case, for the indie merchant, those long haul contracts would be the exception rather than the rule.

It's just that atpollards' model makes some sense, and I'm looking to see how it can be made to work while taking into account the customer's likely preference for the fast/cheap option over the slow/expensive option.

In a TU where ships are small and scarce, I can imagine someone paying the big money to a free trader to go 3 parsecs on the grounds that it's the only ship available. But if there's any kind of traffic at all, I'm inclined to lean on the idea that normally, cargo and passengers will be available for one jump only, whatever the capability of the ship is: A jump 3 ship would be equally able to get passengers for 1,2 or 3 parsec jumps, while a jump 1 ship would only ever be offered the 1 parsec cargos.

 

[robject]

I've always understood that the book 2 rules provide for calculating cargo & passengers for a specific jump as opposed to an ultimate destination. I don't have the book in hand.

I have, too, but I don't remember the rules enforcing that.

 

[jawillroy]

"Jawillroy, your comments about passengers is somewhat valid."

Ah! Damned with faint praise.

" If we look at a "modern model", based on airline routes, it becomes quickly clear that the faster J-3 boat will be able to charge waaaay more for its "

An old argument, valid, which can equally be said to break or fix the rules depending what side of the fence you're on. I'm ill inclined to argue either way, because life is short.

"Unfortunately, the rules do not specifically state that the High Pass ticket costs more on a J-3 boat to a world J-3 away"

I think that the rules do specifically state that a passage costs the same, without regard to distance, per jump. But IYTU, one is free to change ANYTHING, so if you think the rule is broken, fix it. I think that fixing the rule unbalances the game, personally.

 

[Major B]

"Unfortunately, the rules do not specifically state that the High Pass ticket costs more on a J-3 boat to a world J-3 away"

I think that the rules do specifically state that a passage costs the same, without regard to distance, per jump. But IYTU, one is free to change ANYTHING, so if you think the rule is broken, fix it. I think that fixing the rule unbalances the game, personally.

IMTU I've treated the various passages players receive or buy as something akin to an airline voucher. It can be used to book passage, but regular carriers only accept a certain number of vouchers or will have blackout dates and other restrictions (depending on whether I want the characters to get where they want to go easily).

If the players are willing to pay the full price for a berth they have more freedom of maneuver.

 

[jawillroy]

IMpTU, the High Passage and the Kcr-per-ton cargo fee is the gold standard by which the TAS props up the Old Imperial Credit in the interstellar economy and keeps trade and travel between stars affordable. I know, it's only rock and, er, a handwave but I like it.)

If I don't want it to be easy for PCs to get from Heah to Theah, I just shrug and say "Station agent says y' cain't get theah from heah - there isn't but one ship comes through that stops at Wapapitame, and it's not due for another two weeks, and that's if they're on schedule..."

 

[dean]

LTL versus Direct Shipment

I think that the J-1 vs. J-2 ship argument is almost apples-to-oranges, especially as it relates to cargo.

Our modern tractor-trailer model of product delivery is a much closer approximation of cargo movement than the airline model (although if there were a J-5 or J-6 cargo ship available that would be the equivalent).

If you have a consignment that will fill a cargo container (ship) and it can be reached in one jump, it would not be too difficult to find a carrier at a good price to transport the loads. This is comparable to finding an independent trucker who is not necessarily otherwise committed to a scheduled contract.

If you create these kinds of loads all the time, in the interests of both your business and the customer's needs, you'd contract it out to a major carrier that has the resources to carry as many loads as you generate, in the most efficient manner possible.

Now, if your product is not something that fills a container, and the price (demand) for the product does not allow it to be shipped direct at a reasonable cost, the most useful alternative is via a location-to-location carrier. (A modern equivalent is Yellow Freight in the US). These are companies that maintain small freight centers wher the freight is forwarded until a ride can be found headed to the end destination. Movement is typically slower as the freight can (and does) stop and change carriers at successive freight centers. Often, these carriers contract independent carriers to move a large amount of common freight across a greater distance, and then use their own smaller tandem trailers to deliver the freight to the end destinations, often consolidated with other diverse shipments going directly to one destination. Out of the way deliveries are also often delivered via an independent carrier.

In Traveller, I can see J-1 and tramp freighters being a vital link in these operations, probably working all the "off-the-beaten-path" loads for these LTL shippers. Again, these companies usually want to keep their equipment locally (not scattered across the region) as each freight center has it's own inventory, so the independents would be hired to ship a diverse load of freight across a series of J-1 links, dropping cargo off and picking it up at the facilities of one or more of these companies freight centers.

More time sensitive shipments would demand a higher rate to ride the speedier ships.

Happy Travelling!

 

[robject]

IMTU, traffic is so rare that indeed, life is short, and therefore the rules aren't worth worrying about (when they are worth it, then it's time to buy GT: Far Trader or whatever that book is called).

Traffic IMTU has been getting sparser and sparser since I started playing Traveller 12 years ago. It started on the low end to begin with, but assumed that places like Mora and Regina were ultra-busy. But now, I've got numbers like this for "bustling":

Per hour on Mora: 10 ships departing, 10 ships arriving, and 50 ships on the ground.

Or less...

 

[jawillroy]

I forget who it was, Leroy Guatney maybe? who had the JTAS article which dealt with ship traffic from world to world - there was a table which referenced world population with starport type: for an A port on a pop A world he'd have 10d6 ships in port, for a C port on a pop 6 world he'd roll 4d6; for D port on a pop 4 world he'd roll 1 die, and so on. I forget what frequency the turnaround was for him, but it sounds like it's in line with your ship populations.

 

[robject]

I forget who it was, Leroy Guatney maybe? who had the JTAS article which dealt with ship traffic from world to world - there was a table which referenced world population with starport type: for an A port on a pop A world he'd have 10d6 ships in port, for a C port on a pop 6 world he'd roll 4d6; for D port on a pop 4 world he'd roll 1 die, and so on. I forget what frequency the turnaround was for him, but it sounds like it's in line with your ship populations.

I vaguely recall something like that, I think.

Most TUs, I think, subscribe more to the Big Traffic model in principle.

 

[far-trader]

I forget who it was, Leroy Guatney maybe? who had the JTAS article which dealt with ship traffic from world to world...

Yep, good recall The article was titled "Port to Jump-point" in JTAS 22.

 

[Supplement Four]

Most TUs, I think, subscribe more to the Big Traffic model in principle.

MTU uses the moderate traffic principal. :devil:

There's enough traffic to support trade. And, "travellers" are a class of citizen all by themselves. But, your average, everday joe doesn't travel from world to world. It's too expensive--too time consuming.

This isn't Star Wars with your granny's spaceship hopping from world to world.

I view it like ocean trade today in RL. Not too many people are merchant seamen, but there is a thriving business of goods being transported aboard vessels.

"Travellers" in my game still hold some mystique in the eyes of some homeworlders, but they're common enough that it's not an "event" when a starship lands.

 

[dccarles]

I posted some useful statistics for a 'world' based on Australia in another thread. For simplicity I'll reprint them:

Fortunately, I went exploring in the Real World, and I discovered a planet in our system that offers an ideal example: Auzworld.

---
Said planet Auzworld (all credits Imperial)
* Is a TL 7 desert world with a type E starport, and a population of 20.4 million,
* Has a GDP of BCr306, exports BCr55.6, and imports BCr60.8,
* Cannot meet its own energy needs, and imports much of its high-tech equipment,
* Has a merchant marine capable of carrying 3.0 million Imperial displacement tons of cargo. (Passengers and high-priority intrasystem cargoes are usually carried by space plane, which skews this number significantly,)
* Spends 2.4% of its GDP on defense.

There will be some necessary apples-and-oranges comparisons made here, seeing as Auzworld's shipping doesn't include its fleet of fast space planes and the economy is presented in terms of GDP, not GNP. However, if we're going to make any kind of sense of the value of commerce raiding, we need to start somewhere.
---

(Yes, I converted all AusDollars to Imperial credits. All data from the CIA world facts page. Please don't complain about converting figures directly from a continent to a planet; we're looking for ballpark numbers. Or, in the case of Auzworld, cricket ground numbers.)

I chose Australia because it's a continent of its own (so road traffic doesn't make the trade numbers inapplicable), industrialized, and has a decent-sized healthy economy. Furthermore, being mostly desert, it is dependent upon trade to meet some of its basic needs.

3.0 million tons of shipping servicing Auzworld sounds like a lot. (Remember, that's cargo capacity, not ship tonnage.) Assuming a trade cycle of sell/buy at world - jump - sell/buy at next world - jump, only one quarter of it will be in the system at any one time. In reality, less will, because some starships may service more than two planets. Call it, oh, 15%. That's still 450kdt of cargo moving through the system in any given week.

We can assume, then, that Auzworld is regularly serviced by several very large bulk carriers, along with the usual panoply of smaller starships. (The CIA World Fact Book gives a breakdown of ship types in Australia's merchant marine, with 52 ships able to carry 500 dt of cargo or more.)

Where to go from here depends upon whether you're living in a small-ship universe or a large-ship one. I'm going to make yet another assumption and assume that half the cargo is carried by big ships (500 dt or more of cargo) and half by small ones. In your Traveller universe, of course, your parsecage will vary.

This means that the average 'big ship' (assuming 52) will carry 4326 dt of cargo, with the median likely skewed downward. Carrying an average (call it) of 200 dt of cargo, there'll be 1125 small ships servicing Auzworld every week in intersystem trade.

There is, of course, plenty of room for massaging these figures. You can safely change some of them by an order of magnitude or so. If you think 1125 small ships is way too many, assume the existence of very big bulk carriers (carrying 30kdt of cargo or more) in large numbers.

--Devin